Telephone system



Jan, 20, 1925.

1 11,523,429 .c. w. KECKLERET AL TELEPHONE SYSTEM 3 Sheets-Sheet 1 Filed Oct. 1920 1 1 V In l/fliO/"S: Char/es WffeM/er Jack E 00M C. W. KECKLER ET AL TELEPHONE SY S TEM 3 Sheets-Sheet 2 Filed Oct. 1920 Char/es M fleck/er Jack Ffluhl.

Jam. 20. 19 5. 1,523,429

c. W. KECKLER ET AL I TELEPHONE SYSTEM Filedpoot. 29', 0 6 Sheets-Sheet. 5

Fly. 3.

Patented Jan. 20, 1925.

.UNITED STATES fiZMze P T E NT 0 p y onAnLns wfxnoxnnn, "or nnw'AnK, AND JACK r. DAHL, or 'EAST ORANGE, new JERSEY, ASSIGNORS T0 WESTERN ELECTRICICOMPANY, INCORPORATED, or new YORK, n. 2., A ooarona'mon or new YO'RK.

TELEPHONE SYSTEM.

Application filed October 29, 1920. Serial No. 420,445.

To all whom it may concern:

Be it known. that we, GHARi Bs V. Knox- LER and J AOK F.,DAHL, citizens of the United States, residing at Newark, in the county of Essex and State of New.Jersey,.and at East Orange, in-the countyof Ess'fex, State of New Jersey, respectively, have invented certain new and useful Improvements in Telephone Systems, of which the following is a full, clear, concise, and exact descr1pt1of1.

This invention relates to improvements in telephone systems and has particular reference to. an operators impulse sending equipment employed for controlling the successive operation of a series of selective switches utilized in establishing-a call.

An object of the invention is to provide an improved arrangement of circuits and ap paratus whereby a number which it 1s desired to call may be accurately registered and stored, and selective switches subsequently controlled by impulses .transmitted in accordance with theregistration made.

A feature of the invention is the provision of a magnetically controlled register in which contacts of a plurality of series of: contacts are selectively and successively operated under the control of a single set of digit keys and mechanically held in their operated positions.

Another feature is concerned with a circuit arrangement for controlling the transmission of series of direct impulsesto selec tive switches in accordance with the setting of contacts of the various series in said register.

A further feature is the association with each series of contacts of the register, of.

a group of lamps so arranged that upon the successive depression of a number of digit keys and consequent operation of a contact of each series, a corresponding lamp of each group will be lighted whereby the operator may verify the number set up.

In the drawings. Figures 1 and 2, with Figure 2 at the left of Figure 1, illustrate diagrammatically a preferred embodiment of the circuit arrangement for carrying out the invention. Figure 3 is a fragmentary perspective view of the register employed.

The invention is particularly adapted for use at manual switchboards such as are installed at private branch exchanges whereby the operator thereat may transmit direct impulses to full mechanical exchanges, but it is to be expressly understood that the invention is not limited to such use, further than is speclfically indicated in the claims appended hereto.

Referring to the drawings and more particularly to Figures 1 and 2, there is shown a single set of digit keys 1 to-10 which are e of the non-locking type and adapted to be actuated, by the operator at whose position the keys are located, to operate a plurality of magnets 1 to 10, each of which is individual to one ofsaid keys, These magnets form a part of the register which further includes a plurality of series of contacts A to H, each series havingits contacts arranged in a vertical row and having as many contacts as there are digit keys and magnets. Thus, the series A has contacts a to a, the series B contacts 6 to 6 and so on. In Figure 2, eight series of cont-acts are indicated whereby eight series of impulses may be stored and sent but it is to be under:

stood that numbers having a lesser number of digits may also be called. In addition to the ten contacts of each series there are provided the normally closed contacts a. to h each of which is opened when'a contact in the series with which it is associated is operated, as will more fully appear.

Cooperating'with the register is a means whereby the operator may verify any number set up therein. This means preferably comprises a plurality of groups of indicating lamps A to H each group having a number of lamps corresponding to the number of contacts in a series. When any particular contact of a series is operated by the depression of a digit key and consequent energization of the magnet individual to said key, the lamp in the group associated with said series of contacts and corresponding to the particular operated contact in said series, is lighted whereby the operator may ascertain if she has operated the correct digit key. 1

After each operation of a key, a stepping magnet 11' is energized to associate the single set of magnets 1 to 10 with the next suc ceeding series of contacts so that the next depression of any one of the digit keys will result in the operation of a corresponding contact in said succeeding series. At the termination of the operation of the keys 20 ure.

representing the various digits of a called number, the operator inserts the plug 12 (see Fig. 1) of a cord circuit into the ack 13 of an idle trunk leading to a machine switching office and then actuates the start key 14 which, in a manner to be presently described in detail, causes the transmission of direct impulses in accordance with the setting bf the register to the pulsing relay'lo associated with a switch located at said switching office. t

The register, which is shown structurally in Figure 3, preferably comprises a shaft 16 provided with a ratchet wheel 16 adjacent its lower end by means of which the shaft is on one side of the casing 18 of the register and each has associated therewith an operating rod 19 provided with a plurality of lugs 20. To operate the rod 19 so as to open the normally. .closed contacts associated therewith,a number of rocking levers 21 have 'adjacent ends engaged with the lugs 20 and are pivoted contiguous to said ends. The

opposite end of each lever is normally en-' gaged by a spring pressed latch 22 slidably mounted in the wall of the casing 18 and adapted to be disengaged from its.r'espe ctive lever by the energization of the magnet in the group 1' to 10 with which it is associated. Thus, assuming that the magnet 1 is energized by the depression of the digit key 1, the uppermost latch 22 will be at- .tracted to release the inner end of the lever engaged thereby, whereupon, under the influence of a spring 23, said lever will be 4 moved about its pivot to force the rod 19'; upwardly so that the upper end of said rod will open contacts a, The inner end of the lever 21'being connected to the normally open contacts a, it will be obvious that the 0 movement of the lever about its pivot wil l'.

also cause said contacts a to close. Upon the release of magnet 1 due to the release of key 1, the latch 22 is restored-by its spring so that the outer end will be in the path of 5 upward movement of the inner end of the lever21 and thus prevent its return to normal position until the register is restored. Llkewlse, should anyone of the other magnets of the set including magnet 1 be energized, its corresponding latch 22 is operated to release the engaged lever 21 with the result that the rod 19 is operated as before described and the normally open contacts 'associatedwith said lever are closed and main- 66 tained in such position.

As will later appear, upon energization of one of the magnets 1 to 10 the stepping magnet 11 operates'to rotate shaft 16 one step to associate said magnets with the next succeeding set of latches 22. Upon the first The restoration of the register after all the impulses have been transmitted, is accomplished by the energization of the restoring and releasing magnet 25 which, in attracting the armature 26, simultaneously releases ratchet wheel 16 to permit the shaft 16 to return to normal under the in fluence of the spring 17 and elevates a disk or plate 27 slidable on said shaft. A plurality of restoring members 28 have their lower ends ii engagement with said disk and are moved in an upward direction when the disk is raised. Each a-estoring number is slotted to receive pins 29' carried by the leversv 21 whereby the actuated levers are moved toward their normal positions. In so doing, the associated latches 22 are forced inwardly until the inner ends of the levers have passed beyond the outer ends of the U latches whereupon the latches restore to hold the levers in their normal positions. The restoration of the levers permits rods 19 to return tonormal thus closing the con tactsa, I), 0 and so forth. The closed contacts in series A to H are also opened by.

the return of the actuated levers 21 to normal.

It is believed that the following detailed description of the operation will enable those skilled in the art to fully understand the invention.

Let it be assumgdthat the first digit of a desired number is 2. i The operator at whose position the equipment is located depresses digit key 2 whereupon a circuit is established for the magnet 2 of the register extending from grounded battery through the armature and contact of magnet ,11, the winding of magnet 2 and the upper contact of the key to ground. Magnet 2 energizes and, with the register in its normal position, thereby releases the associated lever 21 as previously described, to cause the closing of the contacts a and the opening of contacts Upon the closure of the upper contacts ofthe set an obvious circuitis established for the second lamp in the group A and this lamp ,is lighted to indicate to the operator that the proper digit key has been depressed. The operation of the digit key 2 also establishes an obvious energizing circuit through the winding of magnet 11 and the lower contacts of said digit key whereby the magnet is energized to cause shaft 16 to rotate Inn llt)

to position the group of magnets 1' to 10' in association with the next succeeding series of contacts 13. When the magnet 11 energizes the circuit for magnet 2' is opened at the armature and contactof magnet 11 and magnet 2 then releases. With the off normal contacts 24 closed, an obvious circuit is then established for the pilot lamp 24 The operator then depresses another key corresponding to the second digit'of the desired number whereupon one of the magnets 1. to 10' is again energized to cause the closure of one of the b contacts and the opening of the contacts 6 The magnet 11 is again energized to rotate shaft 16 one step so that upon the depression of-another digit key contacts in series C will be operated. In each instance, lamp is lighted in the group corresponding to the series of contacts in which certain contacts are opened and closed by the operation of a digit key. It will thus be seen that'the operator may verify the number set up in the register before actuating the start key 14. The operator continues to press digit keys .until the other digits of the desired number are recorded in the register and if, during the process of setting up the number, a mistake should be made by depressing the .wrong digit key, the operator may restore the register to normal by depressing the release key 30 (see Figure 1) which closes an obvious circuit for the restoring and releasing magnet 25. Upon energization, magnet 25 looks up through the off normal contacts 24 until the register shaft again reaches its normal position whereupon the locking circpit of said magnet is opened.

Following the operation of the several digit keys, the operator then inserts plug 12 of a cord circuit into a jack 13 of an idle trunk leading to a machine switching office.

The start key 14 is then actuated and establishes an obvious circuit for relay 31 which, upon energization, locks up through its front contact and right hand armature to ground at the off normal contacts 24. The

closure of the left hand contacts and armatures of relay 31 closes a circuit for pulsing relay 15 which forms a part of a selective switch located at said oflice, said circuit 'extending from grounded battery through the right hand winding of said relay, the ring contacts of jack 13 and plug 12, the contact and inner left hand armature of relay 31, the normally closed contacts of the inner left hand armature of relay 32, resistance 33,

. outer left hand armature and contact of re-.

lay 31,-the tip contacts of plug 12 and jack 13, and the left hand winding of relay 15 to ground. This provides a holding circuit for relay 15 through the resistance 33 whereby said relay will remain energized until impulses are tra nsmitted to operate the selec tive switch. The operation of key 14 also establishes a circuit extending from ground throughthe lower contacts of said key, the wiper 34 in position 1 of the switch X and the contact, armature and winding of the stepping magnet MM of said switch to grounded battery. Said magnet is energized but does not operate to step the wipers 34, 35, 43 and A of switch X to position 2, in which position the circuit for magnet MM is opened and said wipers come to rest, until the key l-l is released to open the circuit for said magnet. Said wipers are then stepped upon the back stroke of the armature of magnet MM in a manner well known in the art.

A circuit is now established traceable from grounded battery through the wiper 35 of switch X, the middle right hand armature and contact of relay 36, winding of relay 37, back contact and outer left hand armature of relay 32, and conducting segment of the interrupter 38 to ground. .The relay 37 energizes to establish a circuit for relay 32 and a locking circuit for itself which is traceable from ground through the armature and contact of relay 3?, windings of relays 32 and 37 and from thence over the previously described circuit for relay 37. This energizing and holding circuit for relay 32 and locking circuit for relay 37 is, however, ineffective as long as the brush of the interrupter 38 is in engagement with a conducting segment thereof as it will be apparent that, at this time, relay 32 will be shunted by said interrupter. As soon as the brush of said interrupter engages an insulated segment this shunt is removed and relay 32 energizes to open the original holding circuit for the relay 15 through resistance 33. To maintain said relay 15 energized, a second pulsing interrupter 39 is provided and the insulated segment thereof so arranged that when the brush'of interrupter 38 is in engagement with an insulated segment thereof the brush of interrupter 39 will engage a conducting segment. It will thus be seen that as'soon as an insulated segment of interrupter 38 is engaged by its brush, the brush of interrupter 39 will be resting upon a conducting segment and a holding circuit will therefore be established for relay 15 extending through the front contact and inner left hand armature of relay 32. As the interrupters 38 and 39 rotate in unison and the brushes thereof alternately engage conducting segments, it will be obvious that upon the engagement of the brush of interrupter 38 with the next conducting segment a circuit will be established from ground through Jsaid interrupter the outer left hand armature and front contact of relay 32 and the winding of stepping magnet MIVP of the switch Y to grounded battery. This magnet is energized to step the wipers 40, 41 and 42 of said switch to position 2 and the circuit for said magnet is opened as soon as the next insulated segment of interrupter, 38 engages its brush. During the interval that the energizing circuit for magnet MM is established, an insulated segment of interrupter 39 is in engagement with its brush and the circuit for relay 15 is thus opened to cause the same to release whereby the switch with whicl1'said relay is associated responds to the impulse in a manner well known in the art. A conducting segment of the interrupter 38 is next engaged to again establish the 'stepping circuit for the magnet MM which operates to step its wipers to position 3 and at the same time the circuit-for relav 15 is again established through the pulsing interrupter 39. This operation continues so thatimpulses are transmitted to the rela 1:) as long as relay 32 remains energized. The circuit that is established for stepping magnet MW of switch X- by the energization of 'relay 32 does not cause said magnet to step its wipers 34, 35, 43 and 44 from their second positions since, as before explained the ai'ipei's are stepped upon the back stroke of the magnet.

This permits all of the impulses of the first series to be transmitted before the wipers 'of switch X are stepped preparatory to the transmission of the impulses 'of' thcfnextseries. At the time of the movement of wiper 43 of switch X to position 2, a circuit is extended from ground through said wiper to the conductor 45 which is connected to r the contacts of theseries A. In the same manner the next succeeding seven terminals engaged by wiper 43 are connected, respectively, to conductors associated with the contacts of the series B to H but, lor the sake of simplicity and economy of space only one of these conductors 46 is shown, this latter conductor being associated with the last series H. Connected to the contacts a to, 1: of all of the series is a tommonconductor 47 one end of which is connected to the second terminal over which Wiper 42 of switch Y passes. Likewise, other contacts a to [L2 of the several series have a common conductor 48 which is connected to the third terminal associated with wiper 42. In the same manner similar contacts of all of the series are provided with common conductors which are connected tothe remaining terminals associated with wiper-42.

Under the assumption that the operator first. depresses digit ke' 2 wh n setting up ihe called number with the result that.

contacts a of series A are closed, the circuit for magnet MM will be closed twice through the interrupter 38 to step the wipers of switch Y to position 3. With the wipers of switch X in'position 2, a circuit is now established from ground .throughthe wiper 43, the conductor 45, the lower contacts of the set a, the conductor 48, wiper 42 in popreviously described.

ing circuit is established for relay 15 throughresistance 49 and the front contact and outer right hand armature of relay 36. It will thus be seen that should the brush of interrupter 39 engage'an insulated segment before relaly 32 releases 1ts armatures,

relay 15 will be prevented from releasing by the holding circuit through resistance- 49 and therefore no more impulses will be transmitted to relay 15 after the wiper 42 has reached position 3. The energization of relay 36 also establishes a self-interrupting stepping circuit for magnet 'MM through the wiper 40 and .the front contact and inner right hand amature of relay 36. Magnet MM will therefore op-" era'te to step the wipers of switch Y to their normal positions whereupon the looking circuit for relay 36 through wiper ,41 is opened and relay 36 releases. In the meanwhile, upon the deenergization of relay 32, the circuit for the magnet MM through the right hand ar'mature' and contact of relay 32 is opened and this magnet then releases to step the wipers of switch X to position 3.' After the release of the relay 36, the holding circuit for'relay 15 is again maintained through the resistance 33 and the make-before-break contacts of relay 32.

With switch X in position 3 and switch Y again in its normal position, relay 37 is once more energized as soon as the brush. of

interrupter 38 engages a conducting segment, the energizing path being the same as The operation of transmitting impulses to relay 15 then continues in the same manner as above set forth, the contacts b to 6 of series B'being now associated with switches X and Y. In this manner eight series of impulses may be transmitted to relay 15 if desired and at the termination of these impulses switch X will be stepped from position 9 to position 10. However, let it be assumed for the moment that only three series of impulses were transmitted. In this instance, only contacts of series A, B, and C were operated upon the depression of three of the digit keys and therefore only the normally closed wipers of switch X until the same reach position 10, in which position said wipers would be if eight series of impulses had been sent;' p

With wiper 43 in position 10, a circuit is established for the restoring and releasing magnet 25 extending from ground through wiper 43 and winding of said magnet to grounded battery. This magnet energizes with the previously described results and looks through its right hand front contact and armature to ground at the off normal contacts 24. In attracting its left'h'and' armature, a circuit is closed extending from ground at wiper 43 in position 10, left hand armature and contact of magnet 25, wiper 44 and the contact, armature and winding of stepping magnet MlVP to grounded battery. The latter magnet again operates to step the'wipers to the next position 11 whereupon said stepping magnet finds a ground through the wiper 44 and again operates to step switch X to normal. When the shaft 16 of the register returns to normal, as previously described, the off normal contacts 24: are opened to break the locking circuits for relay 31 and magnet 25 which thereupon release, The circuit for pilot lamp 24 will also be extinguished. By this time the impulses t ansmitted from the sending equipment will have operated the series of switches at the machine switching ofiice to extend the call to the desired line. The release of relay 31 opens, at its left hand armatures and front, contacts the holding circuit for'rel-ayr15 and closes its make-before-break contacts whereby the cord circuit is connected, for conversational purposes, to the called line. The operators sending equipment is again in its normal position and ready for another call.

What is claimed is:

1. In an electrical signaling system, a single set of digit keys, a register for successively registering a plurality of operations of said keys, said register comprising a rotatable spindle carrying a plurality of magnets each individual to and operable by one of said keys, a plurality of rows each comprising a plurality of sets of contacts each individua to and operable by one of The stepping said magnets, means operable in accordance with the setting of said register for transmitting impulses, and. means controlled by the operated contacts for verifying the plurality of operations of said set of keys.

2. In an electrical signaling system,; a

single set of digit keys, a register comprlsing a plurality of series of contacts, means under control of said keys for operating contacts of said plurality of series to register the operation of said keys, a switch having terminals upon which a certain electrical condition is placed in accordance with the operation of said contacts, means for successively associating said switch with said plurality of series of contacts, means for transmitting impulses each time said switch is associated with a series of contacts,

andimeans operable to prevent the operation of the last named means when said switch engages a terminal thereof to which said electrical condition has been applied.

3'. In ag electrical signaling system, a single set of digit keys, a register comprising a plurality of series of contacts, means under control of said keys for operating con tacts of each series to register the operationof said keys, a switch, a second switch, means for operating the first named switch to associate said second switch with one series of contacts, means thereupon operable to transmit impulses in accordance with the, ope-ration of the contacts of said one series, and means operable at the termination of the operation of said last named means to actuate said first named switch to associate said second switch with a succeeding series of contacts.

4. In combination, a single set of digit keys, a register. including a plurality of series of contacts and means for successively operating contacts in each series in accordance with the'actuation of said keys, a trunk 100 line, means for transmitting impulses over said trunk line, switches associated with said register and cooperating to control the operation of said transmitting means in accordance with the operation of contacts in we said plurality of series, and means for simultaneously connecting said transmitting means to said trunk line and for starting the operation of said switches.

In witness whereof, we hereunto subscribe U0 our names this 23rd day of October A. D.,

' CHARLES W: KEGEER.

" JAGKED. p 

